A variable voltage controlling mode of a Low direct current-direct current (DC-DC) Converter (LDC) for a hybrid vehicle is performed to determine an output voltage of the LDC based on information regarding a state of charge (SOC) and temperature of a battery and to control the battery toward a target SOC based on a road driving condition and a vehicle state. However, such a variable voltage controlling mode of the LDC encounters frequent charging and discharging states of a battery, thereby causing energy dissipation, and degrading component efficiency of the battery or LDC.